Field of the Invention
The invention relates to a cooling circuit for the temperature control of at least two heat sources, in particular having a heat exchanger for cooling a coolant, with at least one thermostat, with a first cooling branch and a second cooling branch, wherein in the first cooling branch, the first heat source and the heat exchanger are arranged, and the second heat source is arranged in the second cooling branch, wherein the thermostat comprises a mixing chamber which is flowed through by the coolant.
Description of the Background Art
In motor vehicles, cooling circuits are used to carry away waste heat and to maintain the individual components at an optimum operating temperature level. Waste heat is generated, for example, by the combustion engine or the power electronics used in hybrid vehicles and electric vehicles.
To continue to use the waste heat advantageously, systems are known which specifically use the waste heat of the exhaust system for generating electrical or mechanical power. These so-called waste heat recovery systems also require cooling to keep them within an optimum temperature window for operation.
The optimum temperature level in the cooling circuit for cooling the secondary heat sources, which are defined as all heat sources other than the internal combustion engine, is usually below the optimum temperature level in the cooling circuit for cooling the primary heat source, which is configured to be the combustion engine.
Advantageously, therefore, a cooling circuit is used which makes it possible to provide different temperature levels for different heat sources.
For this purpose, solutions are known in the prior art which provide for a separate additional cooling circuit, which is operated at a different temperature level than the cooling circuit for the internal combustion engine. Solutions are also known which have a plurality of branches, which can be flowed through by coolant at different temperatures.
US 2013/0152880 A1 discloses a thermostat housing which allows for an optimized coolant flow. The thermostat housing has a coolant intake and a coolant outlet and inside, further comprises two thermostats. The at least two thermostats have staggered opening temperatures. The first thermostat controls the flow of coolant through the thermostat housing when the temperature of the coolant is within a temperature window compatible with the opening temperature of the first thermostat.
Moreover, JP 2011-169191 A discloses a system for carrying away the heat from an internal combustion engine which has sufficient heat dissipation properties to dissipate the heat created from the combustion engine, said heat being produced by a high load of the engine.
A disadvantage of the solutions in the prior art is in particular, that sufficient removal of the heat is not given when multiple heat sources are integrated in the cooling circuit. Moreover, the temperature stability of the individual heat sources by previously known controllers in the cooling circuits is not sufficiently provided.
For solutions with multiple branches, it is particularly disadvantageous that a high construction outlay must be pursued to ensure sufficient cooling for the primary heat source and the secondary heat sources at any time during operation. Moreover, the heat loss of such solutions is high, thereby decreasing the efficiency of the entire system. The merging of the individual branches is also problematic because, depending on the supply location, disadvantages in terms of temperature control of the individual heat sources may arise.